Vestibular testing in comatose patients

The analysis of vestibular responses in a comatose patient often provides the critical information for making a correct preliminary diagnosis and directing the subsequent laboratory evaluation. Because of some uncertainties about what is being tested with the various bedside maneuvers that are used to elicit vestibular responses, we review the physiologic basis for the oculomotor responses that occur with head rotation or with caloric stimuli. We further urge precise and unambiguous terminology to describe both stimulus and response. We suggest using physiologically well-defined terms such as vestibulo-ocular reflex and cervico-ocular reflex and avoiding potentially misleading terms such as the doll's head and the oculocephalic maneuvers.     

Influence of mesh materials on collagen deposition in a rat model.

Alterations of the extracellular matrix (ECM) with its major component collagen are increasingly discussed as possible risk factors implicated in the development of abdominal-wall herniation. Because of the widespread use of alloplastic meshes for the surgical repair of hernias, an animal study was performed to analyze the influence of various mesh materials on the quantity and quality of collagen deposition. In 60 male Sprague-Dawley rats an abdominal replacement was performed using three different kinds of mesh materials: polyester (PE), a pure polypropylene (PP), and a composite mesh made of polypropylene and polyglactin (PG). A simple fascia suture repair served as control. The count of fibroblasts, the collagen/protein ratio, the type I/III collagen ratio, and the expression of basic fibroblast growth factor (b-FGF) at the interface were analyzed after 7, 21, and 90 days. The ratio of collagen to overall protein (microg/mg) showed significant differences comparing different mesh materials (sham controls 38.44 +/- 16.33 microg/mg, PE 68.5 +/- 23.8 microg/mg, PP 101.6 +/- 32.3 microg/mg, PG 49.6 +/- 11.6 microg/mg at day 90). The ratio of collagen type I/III increased over time in all groups. However, 90 days after mesh implantation the ratio was always significantly lowered compared to the controls. No significant difference was found comparing different mesh materials. The alteration of the scar composition is closely connected to an increased b-FGF expression. b-FGF and count of fibroblasts highly correlated (r =.95) and showed significant elevated levels compared to simple suture repair. The results of our study strongly support the notion that wound healing is affected by mesh implantation. The quality of the ECM deposition as determined by collagen type I/III ratio is impaired in general, whereas the quantity of ECM deposition is markedly influenced by the kind of mesh material.     

Lithium-induced changes in the body mass index

A total of 117 manic-depressives who had been on lithium for a mean duration of 4.7 years were examined before lithium therapy and subsequently at intervals. Information relating to pre-lithium height and weight and current weight were determined and used to calculate the body mass index (BMI) for each individual. Other relevant variables such as age, sex, cumulative lithium dose, duration of therapy, thyroid profile and serum lithium levels were recorded. The results indicated that, although there was a nonsignificant increase in BMI for the whole population, lithium and sex were not significant predictors of any increase in BMI. In nearly 27% of patients BMI actually slightly decreased during lithium therapy. The overall conclusions from this study are that, in the population studied, lithium may not have exerted any pharmacological effects to increase BMI.     

The effect of oxytocin on basal and pethidine-induced delayed gastric emptying.

1. Continuous infusion of oxytocin (0.33 u min-1) accelerated gastric emptying of semisolid TC-99m labelled Chelex-100 resin/oatmeal in 10 healthy volunteers under basal conditions. 2. Administration of oxytocin did not change the pattern of gastric emptying delayed by pethidine. 3. The emptying pattern of semisolid has confirmed the existence of a lag phase.     

CEA and CA 19.9: an evaluation by new statistical technics on a group of elderly patients

New parametric and non parametric statistical methods have been compared in the evaluation of experimental data of CEA and CA 19.9 using a brief program in BASIC. We have found that the distribution of the two markers is the same of that described in literature except for both the means that we have found being slightly higher than that ones described by other authors.     

Hexamethyldisilazane in preparation of retinal tissue for scanning electron microscopy

A new rapid procedure for desiccating frozen resin-cracked retinal tissue for scanning electron microscopy (SEM) which permits air-drying was found to compare favorably with tissues prepared by critical-point drying: Retinal tissue was fixed in 4% phosphate-buffered neutral formaldehyde, dehydrated by means of graded ethanol, embedded in Epon, cracked and washed in propylene oxide. For desiccation, the specimens were immersed in hexamethyldisilazane (HMDS), air-dried and finally sputter-coated. The method is time-saving, gives extended information in SEM, and the number of good specimens is increased.